Method of electric welding



(No Model.)

C. L. COFFIN. v METHOD 0P BLEGTRIG WELDING. No. 427,971. Patented May13', 1890.

'Wo r W62.

UNITED STATES PATENT OFFICE.

CHARLES L. COFFIN, OF DETROIT, MICHIGAN.

METHOD OF ELECTRIC WELDING.

SPECIFICATION forming part of Letters Patent No. 427,971, dated May 13,1890.

Application filed April 24, 1889. Serial No. 308,417. (No model.)

To all whom it may concern.-

Be it known that 1, CHARLES L. 00mm, of Detroit, in the county of Vayneand State of Michigan, have invented a new and useful Improvement inProcess of Electric Velding, of which the following is a specification.

My invention consists in an improved process of electric welding,hereinafter fully described and claimed.

The drawings are vertical sections illustrating the invention, Figs. 1and 2 showing it applied to that process in which an arc is formedbetween carbons on the same side of the articles to be welded, and Fig.3 showing it applied to that process in which a voltaie arc is formedbetween two carbons on opposite sides of the article to be welded.

The first part of my improved process consists in placing the parts tobe welded together in close proximity to the voltaic are withoutbringing them in actual contact therewith, and another part of myprocess consists in protecting the parts to be welded and the are by ajacket.

In Fig. 1 F and E represent the articles to be welded, and O 0 representtwo plate carbons connected by the wires P P with one pole of agenerator of electricity, and 1-3 represents a carbon connected by thewire D with the other pole.

A represents a jacket of refractory material, as asbestus orfire-brick,located 011 one or both sides of the articles F and E, and the outerskin of this jacket may be of some other material, as carbon. (Indicatedat G and ll.)

In Figs. 1 and 2 the jacket A incloses the points of the two carbons Band C and rests upon the articles E and F, which are to be welded.

In Fig. 2, as the are is formed between two carbons both of which areover the article to be welded, it is only necessary to protect the upperside of said articles with the jacket, and therefore the jacket A isentirely on the upper side of the articles F and E, and the carbons Band 0 pass through holes respectively at the top and side of the jacket.

In Fig. 3 the carbons B and C are above and below the articles F and Eto be welded, which pass through a space between the upper and lowerpart of the jacket.

It will be noticed that the edges of the artieles E and F to be weldedare in no case directly within the voltaic are, but are in closeproximity thereto, and that the heat of the are is concentrated andprotected from dissipation by the jacket A, whereby burning the edges ofthe articles F and E through the intense heat of the voltaic arc isavoided, but yet they are readily brought to a plastic condition andthey are then pressed together in any of the well-known modes to formweld.

\Vhat I claim as my invention, and desire to secure by Letters Patent,is-

The herein-described process of electric welding, consisting in placingthe parts to be welded in close proximity to a voltaic are, protectingthe are and the parts to be welded by a jacket of non-conductingrefractory material, and after sut'iicientl y heating the parts pressingthem together to complete the weld.

CHARLES L. OOFFlN.

Vitnesses:

GEo. H. LOTHROP, ADELAIDE A. ANDERSON.

